FIELD: chemistry. SUBSTANCE: invention relates to terahertz (THz) materials, namely to crystals in demand for use in medicine, pharmaceuticals, customs remote control and other areas. The terahertz crystal according to the invention is characterized by being made on the basis of single-phase solid solutions of the AgCl - AgBr system, containing silver chloride and bromide at the following ratio of ingredients, wt. % : silver chloride - 0.0 to 90.0; silver bromide - 90.0 to 10.0. EFFECT: invention allows to form crystals transmitting emission in a wide spectral range, from terahertz to millimeter, infrared and visible ranges with high optical transparency from non-toxic, non-hygroscopic, plastic materials. 1 cl.